top daily news http://teafotography.com Tue, 20 Dec 2022 16:29:31 +0000 en-US hourly 1 https://wordpress.org/?v=6.1.1 ‘The Milky Way’ wants you to get to know your home in the universe /20242/ Tue, 20 Dec 2022 16:29:29 +0000 /?p=20242 Astrophysicist Moiya McTier’s new book introduces our galaxy from an unusual perspective

Meet the Milky Way in its own words.

The Milky Way: An Autobiography of Our Galaxy takes a tour of our home in the cosmos from an unexpected perspective. Astrophysicist and folklorist Moiya McTier presents herself not as the author, but as the lucky human vessel through which the Milky Way has chosen to tell its story. Then she lets the galaxy take it away, with humor, heart and a huge dose of snark.

The book alternates chapters between science and mythology, reflecting McTier’s dual specialties (her bio says she was the first student in Harvard University’s history to study both). “Many of you don’t realize this, but myths were some of your species’ first attempt at scientific inquiry,” the Milky Way tells us.

The Milky Way is telling its story now because it’s sick of being ignored. Once upon a time, humans looked to the glittering smudge of stars in the sky for insight into when to plant crops or avoid floods. We told stories about the Milky Way’s importance in the origin and fate of the world.

Our galaxy ate it up: For an entity that spends most of its time ripping up smaller galaxies and watching its own stars die, “your stories made me feel loved and needed and, perhaps for the first time in my long existence, more helpful than I was ruinous.” But in the last few centuries, technology and light pollution have pulled humankind away. “At first, I thought it was just a phase,” the Milky Way says. “Then I remembered … that several hundred years is actually a long time for humans.”

So the Milky Way decided to remind us why it’s so important. Its autobiography covers big-picture scientific questions about galaxies, like where they come from (“When a gas cloud loves itself very much,” the Milky Way explains, “it hugs itself extra tight, and after a few hundred million years, a baby galaxy is born. Leave the storks out of it, please.”). It also gets into what galaxies are made of, how they interact with other galaxies, and how they live and die. The book then zooms out to cover the origins and possible ends of the universe, mysteries like dark matter and dark energy, and even humankind’s search for other intelligent life (SN: 8/4/20).

The author takes pains to explain scientific jargon and the technical tools that astronomers use to study the sky. A lot of popular astronomy writing glosses over how astronomers think about cosmic distance or exactly what a spectrum is, but not this book. If you’ve ever been curious about these insider details, The Milky Way has you covered.

McTier’s version of our home galaxy is heavily anthropomorphized. The Milky Way is brash, vain and arrogant in a way that may hide a secret insecurity. Its central black hole is characterized as the physical embodiment of the galaxy’s shame and regrets, a source of deep existential angst. And its relationship with the Andromeda galaxy is like a long-term, long-distance romance, with each galaxy sending stars back and forth as love notes until the two can eventually merge (SN: 3/05/21).

This could have felt gimmicky. But McTier’s efforts to make the metaphors work while keeping the science accurate and up-to-date made the premise endearing and entertaining.

I laughed twice on Page 1. I learned a new word on Page 2. I dog-eared the endnotes early on because it became instantly clear I would want to read every one. I read this book while traveling in rural upstate New York, where the sky is much clearer than at my home outside of Boston. The Milky Way reminded me to look up and appreciate my home in the universe, just like its narrator wanted.

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Ancient ‘demon ducks’ may have been undone by their slow growth /20239/ Tue, 20 Dec 2022 16:28:22 +0000 /?p=20239 Australia once had horse-sized mihirung birds, but the lineage vanished about 40,000 years ago

Giant flightless birds called mihirungs were the biggest birds to ever stride across what is now Australia. The animals, which weighed up to hundreds of kilograms, died out about 40,000 years ago. Now researchers might have a better idea why.

The birds may have grown and reproduced too slowly to withstand pressures from humans’ arrival on the continent, researchers report August 17 in the Anatomical Record.

Mihirungs are sometimes called “demon ducks” because of their great size and close evolutionary relationship with present-day waterfowl and game birds. The flightless, plant-eating birds lived for more than 20 million years.

Over that time, some species evolved into titans. Take Stirton’s thunderbird (Dromornis stirtoni). It lived about 7 million years ago, stood 3 meters tall and could exceed 500 kilograms in weight, making it the largest-known mihirung and a contender for the largest bird ever to live.

Most research on mihirungs has been on their anatomy and evolutionary relationships with living birds. Little is known about the animals’ biology, such as how long they took to grow and mature, says Anusuya Chinsamy-Turan, a paleobiologist at the University of Cape Town in South Africa.

So Chinsamy-Turan and colleagues at Flinders University in Adelaide, Australia took samples from 20 fossilized leg bones of D. stirtoni, from animals of varying life stages.

“Even after millions of years of fossilization, the microscopic structure of fossil bones generally remains intact,” and it can be used to decipher important clues about extinct animals’ biology, Chinsamy-Turan says.

The team examined the thin bone slices under a microscope, detailing the presence or absence of growth marks. These marks provide information on how fast the bone grew while the birds were alive.

D. stirtoni took 15 years or more to reach full size, the team found. It probably became sexually mature a few years before that, based on the timing of a shift from rapidly growing bone to a slower-growing form that’s thought to be associated with reaching reproductive age.

These results differ from the team’s earlier analysis of the bones of another mihirung, Genyornis newtoni. That species — the last-known mihirung — was less than half the size of D. stirtoni. It lived as recently as about 40,000 years ago and was a contemporary of the continent’s earliest human inhabitants. G. newtoni grew up much faster than its giant relative, reaching adult size in one to two years and growing a bit more in the following years and possibly reproducing then.

This difference in how fast mihirung species that were separated by millions of years developed may have been an evolved response to Australia developing a drier, more variable climate over the last few million years, the researchers say. When resources are unpredictable, growing and reproducing quickly can be advantageous.

Even so, that seeming pep in the developmental step of more recent mihirungs was still slower than that of the emus they lived alongside. Emus grow up quickly, reaching adult size in less than a year and reproducing not long after, laying large numbers of eggs.

This difference may explain why G. newtoni went extinct shortly after hungry humans arrived in Australia, yet emus continue to thrive today, the team says. Even though over millions of years, mihirungs as a group seem to have adapted to growing and reproducing quicker than they used to, it wasn’t enough to survive the arrival of humans, who probably ate the birds and their eggs, the researchers conclude.

“Slowly growing animals face dire consequences in terms of their reduced ability to recover from threats in their environments,” Chinsamy-Turan says.

The scientists’ research on other giant, extinct, flightless birds thought to have met their end thanks to humans — such as the dodos of Mauritius (Raphus cucullatus) and the largest of Madagascar’s elephant birds (Vorombe titan) — shows that they too grew relatively slowly (SN: 8/29/17).

“It is very interesting to see this pattern repeating again and again with many large, flightless bird groups,” says Thomas Cullen, a paleoecologist at Carleton University in Ottawa who was not involved with the new study.

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The James Webb telescope spotted CO2 in an exoplanet’s atmosphere /20236/ Tue, 20 Dec 2022 16:27:14 +0000 /?p=20236 It’s the first definitive detection of the greenhouse gas at a planet outside the solar system

The James Webb Space Telescope has gotten the first sniff of carbon dioxide in the atmosphere of a planet in another solar system.

“It’s incontrovertible. It’s there. It’s definitely there,” says planetary scientist and study coauthor Peter Gao of the Carnegie Institution for Science in Washington, D.C. “There have been hints of carbon dioxide in previous observations, but never confirmed to such an extent.”

The finding, submitted to arXiv.org on August 24, marks the first detailed scientific result published from the new telescope. It also points the way to finding the same greenhouse gas in the atmospheres of smaller, rockier planets that are more like Earth.

The planet, dubbed WASP-39b, is huge and puffy. It’s a bit wider than Jupiter and about as massive as Saturn. And it orbits its star every four Earth days, making it scorching hot. Those features make it a terrible place to search for evidence of extraterrestrial life (SN: 4/19/16). But that combination of puffy atmosphere and frequent passes in front of its star makes it easy to observe, a perfect planet to put the new telescope through its paces.

James Webb, or JWST, launched in December 2021 and released its first images in July 2022 (SN: 7/11/22). For about eight hours in July, the telescope observed starlight that filtered through the planet’s thick atmosphere as the planet crossed between its star and JWST. As it did, molecules of carbon dioxide in the atmosphere absorbed specific wavelengths of that starlight.

Previous observations of WASP-39b with NASA’s now-defunct Spitzer Space Telescope had detected just a whiff of absorption at that same wavelength. But it wasn’t enough to convince astronomers that carbon dioxide was really there.

“I would not have bet more than a beer, at most a six pack, on that weird tentative hint of carbon dioxide from Spitzer,” says astronomer Nicolas Cowan of McGill University in Montreal, who was not involved with the new study. The JWST detection, on the other hand, “is rock solid,” he says. “I wouldn’t bet my firstborn because I love him too much. But I would bet a nice vacation.”

The JWST data also showed an extra bit of absorption at wavelengths close to those absorbed by carbon dioxide. “It’s a mystery molecule,” says astronomer Natalie Batalha of the University of California, Santa Cruz, who led the team behind the observation. “We have several suspects that we are interrogating.”

The amount of carbon dioxide in an exoplanet’s atmosphere can reveal details about how the planet formed (SN: 5/11/18). If the planet was bombarded with asteroids, that could have brought in more carbon and enriched the atmosphere with carbon dioxide. If radiation from the star stripped away some of the planet atmosphere’s lighter elements, that could make it appear richer in carbon dioxide too.

Despite needing a telescope as powerful as JWST to detect it, carbon dioxide might be in atmospheres all over the galaxy, hiding in plain sight. “Carbon dioxide is one of the few molecules that is present in the atmospheres of all solar system planets that have atmospheres,” Batalha says. “It’s your front-line molecule.”

Eventually, astronomers hope to use JWST to find carbon dioxide and other molecules in the atmospheres of small rocky planets, like the ones orbiting the star TRAPPIST-1 (SN: 12/13/17). Some of those planets, at just the right distances from their star to sustain liquid water, might be good places to look for signs of life. It’s yet to be seen whether JWST will detect those signs of life, but it will be able to detect carbon dioxide.

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How death’s-head hawkmoths manage to fly straight for miles in the dark /20233/ Tue, 20 Dec 2022 16:15:57 +0000 /?p=20233 The nocturnal insects appear to chart flight paths with the help of an internal compass

Sitting alone in the cockpit of a small biplane, Martin Wikelski listens for the pings of a machine by his side. The sonic beacons help the ecologist stalk death’s-head hawkmoths (Acherontia atropos) fluttering across the dark skies above Konstanz, Germany — about 80 kilometers north of the Swiss Alps.

The moths, nicknamed for the skull-and-crossbones pattern on their backs, migrate thousands of kilometers between northern Africa and the Alps during the spring and fall. Many migratory insects go where the wind takes them, says Ring Carde, an entomologist at the University of California, Riverside who is not a member of Wikelski’s team. Death’s-head hawkmoths appear to be anything but typical.

“When I follow them with a plane, I use very little gas,” says Wikelski, of the Max Planck Institute of Animal Behavior in Munich. “That shows me that they are supposedly choosing directions or areas that are probably supported by a little bit of updraft.”

A new analysis of data collected from 14 death’s-head hawkmoths suggest that these insects indeed pilot themselves, possibly relying in part on an internal compass attuned to Earth’s magnetic field. The moths not only fly along a straight path, they also stay the course even when winds change, Wikelski and colleagues report August 11 in Science.

The findings could help predict how the moths’ flight paths might shift as the globe continues warming, Wikelski says. Like many animals, death’s-head hawkmoths will probably move north in search of cooler temperatures, he suspects.

To keep tabs on the moths, Wikelski’s team glued radio transmitters to their backs, which is easier to do than one might expect. “Death’s-head hawkmoths are totally cool,” Wikelski says. They’re also huge. Weighing as much as three jellybeans, the moths are the largest in Europe. That makes attaching the tiny tags a cinch, though the moths don’t like it very much. “They talk to you, they shout at you a little bit,” he says.

Once the researchers set the newly tagged and slightly annoyed moths free, Wikelski took off after them in a plane. As the insects flew south toward the Alps, a device onboard pinged the transmitters at a frequency related to the moths’ distance from the plane.

While detailed tracking of eight of the moths allowed him to follow the insects for about 63 kilometers on average, he pursued one for just under 90 kilometers. That’s the longest distance that an insect has been continuously tracked, he says. “It’s outrageously crazy work,” he says of the night flights at low altitude. “It’s also a little dangerous and it’s just showing it’s possible.”

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‘Chameleon’ forces remain elusive in a new dark energy experiment /20230/ Tue, 20 Dec 2022 16:14:31 +0000 /?p=20230 A hypothetical fifth force that morphs based on its environs didn’t turn up

A chameleon-like force that shifts its nature based on its environment could explain a major physics quandary: how the mysterious substance called dark energy is compelling the cosmos to expand faster and faster. But a new experiment casts doubt on some chameleon theories, researchers report August 25 in Nature Physics.

The chameleon force would be a fifth type of force beyond the basic four: gravitational, strong, weak and electromagnetic. And like a chameleon changing its colors, the hypothetical fifth force would morph depending on the density of its surroundings. In dense environments like Earth, this fifth force would be feeble, camouflaging its effects. In the sparseness of space, the force would be stronger and long-ranged.

This force would result from a chameleon field — an addition to the known fields in physics, such as electric, magnetic and gravitational fields. A chameleon field with these morphing properties could drive the accelerating expansion of the universe without disagreeing with measurements on Earth.

But it’s a challenge to suss out such a changeling force. On Earth, says astrophysicist Jianhua He of Nanjing University in China, “it’s very, very tiny. That’s the most difficult part.”

So He and colleagues designed a detector to search for a subtle fifth force. A wheel with plastic films attached spins past another film sitting on a magnetically levitated piece of graphite. If a chameleon force really exists, the films spinning by would cause a periodic force on the levitating plastic, pulling it up and down. (Gravity also acts this way, but thanks to the device’s design, it should be much weaker than a chameleon force.)

The team was able to rule out a category of chameleon theories. In the future, the researchers hope to improve their results by chilling their device to allow for more sensitive measurements.

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A new seasoning smells like meat thanks to sugar — and mealworms /20227/ Tue, 20 Dec 2022 16:06:28 +0000 /?p=20227 New research aims to help people get past the ick of eating insects

A spoonful of sugar may help the mealworms go down.

Adding sugars to powdered, cooked mealworms creates a seasoning with an appetizing “meatlike” odor, researchers report August 24 at the American Chemical Society fall meeting in Chicago.

Some insects have been found to be an environmentally friendly alternative to other animal protein because they require less land and water to raise (SN: 5/11/19). But many people in the United States and other Western countries, where insects aren’t eaten widely, generally find the idea of chomping down on bugs unappetizing.

“There aren’t a lot of people ready to fry up a whole skillet of crickets and eat them fresh,” says Julie Lesnik, a biological anthropologist at Wayne State University in Detroit who wasn’t involved in the new research. Finding out how to make insect-based foods more appealing could be key to making them more mainstream.

And one successful insect-based product could have a snowball effect for similar food. “It’s really great that this research is happening, because at any point this might be the thing that people figure out and then it explodes,” says Brenden Campbell, an insect agriculturist based in Eugene, Ore. He has studied mealworms and created a company called Planet Bugs to, in part, make insect-based food products.

In a previous study, chemist In Hee Cho of Wonkwang University in South Korea and colleagues analyzed the odors given off by mealworms that were steamed, roasted or deep-fried. Steamed mealworms produced a sweet smell, like corn, while roasted and fried mealworms released chemicals more similar to meat and seafood.

In their latest work, the team then keyed in on what combinations of water, sugars and cooking time produced a particularly meaty smell, and tested these concoctions with volunteers to figure out which smelled the most appealing.

Using insects ground up or in seasonings, like Cho’s team did, could help people get past their hesitations about eating whole bugs, says Amy Wright, who has written a book on eating bugs. (She, for one, has no qualms. A literature professor at Austin Peay State University in Clarksville, Tenn., Wright used to keep mealworms in her apartment, which she would use in sandwiches and guacamole.)

“There are plenty of things that are disgusting to us, but we have engineered around it,” Lesnik says. “We’re just seeing insects being treated like any other food, and yeah, we’re talking aroma … but that’s what the engineers of Doritos are doing.”

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7-million-year-old limb fossils may be from the earliest known hominid /20224/ Tue, 20 Dec 2022 16:05:38 +0000 /?p=20224 Misconduct allegations over an earlier report on one of the bones hang over the findings

In 2001, researchers unearthed a partial fossil leg bone and two forearm bones in the central African nation of Chad. Those fossils come from the earliest known hominid, which lived around 7 million years ago, and reveal that the creature walked upright both on the ground and in the trees, a new study proposes.

But a lively debate surrounds the fossils, concerning whether they actually belong to the hominid species, known as Sahelanthropus tchadensis, or to an ancient ape, and to what extent either species could have adopted a two-legged gait. These have become vexing questions as scientists increasingly suspect that ape and hominid species evolved a variety of ways to walk upright, some more efficient than others, around 7 million years ago.

Since its discovery, the leg bone has also triggered competing accusations of scientific misconduct and an official investigation by the French government–funded research organization CNRS in Paris.

Previously, skull, jaw and tooth finds uncovered at the Chad site in 2001 and 2004 were classified as remnants of S. tchadensis (SN: 4/6/05). The finds are the only other fossils attributed to the species, though some researchers have also since suggested that those fossils represent an ancient ape instead.

Analyses of the three limb bones show that they belong to the previously identified Sahelanthropus species, say paleontologists Guillaume Daver and Franck Guy, both of the University of Poitiers in France, and their colleagues. And internal and external features of the leg bone indicate that Sahelanthropus walked upright, the scientists report August 24 in Nature. Shapes and structures of the two forearm bones suggest that the hominid moved on two legs through trees while grasping branches with its hands, the team says.

“The Chadian species has a set of anatomical features that clearly indicate that our oldest known [hominid] representative [walked] on the ground and in the trees,” Guy says. It’s hard to tell how efficiently or how fast Sahelanthropus moved on two legs, he adds.

Guy’s team studied 3-D digital models of the fossils derived from CT scans. The leg bone was compared with fossils of ancient apes and other hominids and with modern apes and humans. Traits including thickening of the leg bone’s tough outer layer at key points and the presence of an internal bony projection near the hip joint signal an upright stance, the scientists say.

Fossils from the African site, including the three limb bones, suggest that Sahelanthropus was the earliest known hominid, agrees paleoanthropologist Kristian Carlson of the University of Southern California in Los Angeles, who did not participate in the new study. But exactly how it moved while upright remains unknown, he says. Sahelanthropus exhibits a mix of upper leg and forearm traits that differs from those of living apes and humans, suggesting it adopted a novel posture and limb movements while walking.

Whatever stance Sahelanthropus assumed, it probably resembled that of two other early hominids, roughly 6-million-year-old Orrorin tugenensis and more than 5-million-year-old Ardipithecus kadabba, says paleoanthropologist Yohannes Haile-Selassie, director of the Institute of Human Origins at Arizona State University in Tempe (SN: 9/11/04; SN: 3/3/04). Walking abilities of those hominids remain poorly understood due to limited fossils — a partial leg bone for O. tugenensis and a toe bone for the Ardipithecus species.

Haile-Selassie regards all three hominids as part of a single genus that evolved from around 7 million to 5 million years ago. On that issue, “the debate is open, even between members of our team,” Guy says.

Another debate concerns the upper leg’s internal bony projection that the researchers cite as crucial for standing upright. That trait sometimes appears in modern African apes and occasionally is absent in humans, paleoanthropologist Marine Cazenave of the American Museum of Natural History in New York City and colleagues report in the June Journal of Human Evolution. The presence of this bony growth does not definitively show that Sahelanthropus walked upright, Cazenave says.

Other researchers contend that the leg bone most likely comes from an ancient ape — not a hominid — that may have occasionally walked upright. Shape measurements, including curvature of the fossil’s shaft, closely resemble those of modern chimps’ upper leg bones, University of Poitiers paleoanthropologist Roberto Macchiarelli and colleagues reported in December 2020 in the Journal of Human Evolution.

“There may have been ancient apes that had distinctive types of [upright movement] unlike any living apes, including humans,” says paleoanthropologist Bernard Wood of George Washington University in Washington, D.C., who was a coauthor of the 2020 study.

Here is where charges of scientific misconduct come into play. The 2020 study was based on measurements of the Sahelanthropus leg fossil taken in 2004 by a University of Poitiers graduate student conducting a project on how fossilization affects bones.

That student, Aude Bergeret-Medina, was given access to fossils from the Sahelanthropus site that Daver and Guy’s team had tagged as neither hominid nor, more generally, as primate. She noted that one specimen — the leg bone — looked like it belonged to a primate, possibly an ape. Macchiarelli confirmed her observation. Plans for Bergeret-Medina to cut open the bone to study its mineral content were halted.

Macchiarelli informed his university and CNRS of the fossil’s identity. He spent the next 16 years, he says, sending repeated complaints to those institutions that the Sahelanthropus discoverers were violating codes of scientific conduct by not providing information about the leg bone in scientific papers or talks.

Then, CNRS launched an investigation of possible misconduct by Macchiarelli himself when the 2020 study appeared before the Sahelanthropus team published findings on the leg bone in its possession. No ruling has been made yet.

In supplementary information published with the new study, Guy and colleagues write that they identified the forearm bones among stored fossils after Macchiarelli brought the leg bone’s identity to their attention. Further excavations in Chad were conducted before launching a detailed study of the three limb fossils in 2017, the team says.

But the Sahelanthropus team does not cite Bergeret-Medina — now the curator of the Muséum d’Histoire Naturelle Jacques de La Comble in Autun, France — by name for her role in the leg bone’s identification. The investigators write that “a master’s student in taphonomy” received various fossils for a research internship in early 2004 before those finds had been carefully examined by senior scientists. The student, “seeking expertise,” gave the leg fossil to Macchiarelli who identified it as a hominid, Daver and colleagues say.

That’s incorrect, Macchiarelli contends. Bergeret-Medina initially identified the fossil as a primate’s upper leg bone followed by his confirmation of her observation. No claim was made that the fossil came from a hominid, he says. But without Bergeret-Medina’s insightful fossil observation, the new study would never have happened, Macchiarelli asserts.

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50 years ago, genes eluded electron microscopes /20221/ Tue, 20 Dec 2022 16:04:45 +0000 /?p=20221 Excerpt from the September 2, 1972 issue of Science News

Molecular biologists can now visualize the larger structures of the cell, such as the nucleus and chromosomes, under the powerful electron microscope. But they have not been able to obtain images of genes (DNA) on the chromosomes. Nor have they been able to see RNA … or the intricate details of cell membranes, enzymes and viruses.

Electron m­icroscopes have become much more powerful over the last 50 years. For instance, in 1981, biophysicist Jacques D­ubochet discovered that tiny biological structures super­cooled with ethane could be observed in their natural state under an electron microscope. That finding paved the way for cryo-electron micro­scopy, which scientists use to visualize proteins, viruses and bacteria at the molecular level (SN: 10/28/17, p. 6). Capturing detailed images of genes remains elusive, but scientists are inching closer. In 2021, researchers reported using an electron microscope and the molecular scissors CRISPR/Cas9 to visualize proteins transcribing DNA instructions for two genes into RNA.

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Sleep deprivation may make people less generous /20218/ Tue, 20 Dec 2022 16:03:52 +0000 /?p=20218 A lack of sleep depresses activity in brain regions linked to social behavior, brain scans show

Lack of sleep has been linked to heart disease, poor mood and loneliness (SN: 11/15/16). Being tired could also make us less generous, researchers report August 23 in PLOS Biology.

The hour of sleep lost in the switch over to Daylight Savings Time every spring appears to reduce people’s tendency to help others, the researchers found in one of three experiments testing the link between sleep loss and generosity. Specifically, they showed that average donations to one U.S.-based nonprofit organization dropped by around 10 percent in the workweek after the time switch compared with four weeks before and after the change. In Arizona and Hawaii, states that do not observe Daylight Savings Time, donations remained unchanged.

With over half of the people living in parts of the developed world reporting that they rarely get enough sleep during the workweek, the finding has implications beyond the week we spring forward, the researchers say.

“Lack of sleep shapes the social experiences we have [and] the kinds of societies we live in,” says neuroscientist Eti Ben Simon of the University of California, Berkeley.

To test the link between sleep loss and generosity, Ben Simon and her team first brought 23 young adults into the lab for two nights. The participants slept through one night and stayed awake for another night.

In the mornings, participants completed a standardized altruism questionnaire rating their likelihood of helping strangers or acquaintances in various scenarios. For instance, participants rated on a scale from 1 to 5, with 1 for least likely to help and 5 for most likely, whether they would give up their seat on a bus to a stranger or offer a ride to a coworker in need. Participants never read the same scenario more than once. Roughly 80 percent of participants showed less likelihood of helping others when sleep-deprived than when rested.

The researchers then observed participants’ brain activity in a functional MRI machine, comparing each participant’s neural activity in a rested versus sleep-deprived state. That showed that sleep deprivation reduced activity in a network of brain regions linked to the ability to empathize with others.

In another experiment, the researchers recruited 136 participants online and had them keep a sleep log for four nights. Each participant then completed subsets of the altruism questionnaire before 1 p.m. the next day. The researchers found that the more time participants spent awake in bed, a measure of poor sleep, the lower their altruism scores. That drop in altruism held true both when comparing individuals to themselves and when averaging scores across the group.

In the final experiment focused on Daylight Savings Time, the researchers looked at charitable donations from 2001 to 2016 to Donors Choose, a nonprofit that raises money for school projects across the United States. When the team excluded Hawaii and Arizona, as well as outliers like very large donations, more than 3.4 million donations remained. In the workweek following the time change, total donations, which typically averaged roughly $82 per day, dropped to about $73 per day, Ben Simon says.

There’s always a possibility that some other variable besides sleep is causing this dip in generosity, says behavioral economist David Dickinson of Appalachian State University in Boone, N.C. But this “triple methodology approach” enabled the researchers to draw a convincing line from changes to the brain that appear during sleep deprivation to real-world behavior. “This puts a more comprehensive story on how inefficient sleep affects decisions in this domain of helping others,” he says.

Chronic sleep deprivation in the modern world is a serious problem, Ben Simon says (SN: 3/1/19). But unlike many other large-scale problems — think climate change or political polarization — this one has a ready solution. “If you think about promoting sleep and letting people get the sleep they need, what an impact that could have on the societies we live in.”

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News stories have caught spiders in a web of misinformation /20215/ Tue, 20 Dec 2022 16:02:45 +0000 /?p=20215 The errors probably contribute to the animals’ undeserved bad reputation

Even spiders, it seems, have fallen victim to misinformation.

Media reports about people’s encounters with spiders tend to be full of falsehoods with a distinctly negative spin. An analysis of a decade’s worth of newspaper stories from dozens of countries finds that nearly half of the reports contain errors, arachnologist Catherine Scott and colleagues report August 22 in Current Biology.

“The vast majority of the spider content out there is about them being scary and hurting people,” says Scott, of McGill University in Montreal. In reality, they note, “spiders almost never bite people.”

Of the roughly 50,000 known spider species, vanishingly few are dangerous. Instead, many spiders benefit us by eating insects like mosquitoes that are harmful to people. Even with the rare exceptions like brown recluse and black widow spiders, bites are extremely uncommon, Scott says. Some stories about bites blamed spiders that don’t occur in the area, and others reported symptoms that don’t match symptoms of actual bites. “So many stories about spider bites included no evidence whatsoever that there was any spider involved,” they say.

To conduct the study, Scott and their colleagues analyzed over 5,000 online newspaper stories about humans and spiders from 2010 to 2020 across 81 countries. In addition to errors, the team determined that 43 percent of the stories were sensationalized, often using words like nasty, killer, agony and nightmare. International and national newspapers were more likely to sensationalize spiders than regional outlets. Stories that included a spider expert were less sensationalistic, though there was no such effect from other experts, including doctors.

If people knew the truth about spiders, they could spend less time blaming them for bites and killing them with pesticides that are toxic to many other species, including humans, Scott says. Clearing up the misinformation would be good for spiders, too — especially the one in your house that doesn’t get squashed out of fear. Spiders in general stand to benefit, the researchers conclude, because news helps shape public opinion, which can influence decisions about wildlife conservation.

“Spiders are kind of unique in that they seem to be really good at capturing people’s attention,” says arachnologist Lisa Taylor at the University of Florida in Gainesville, who was not involved in the study. “If that attention is paired with real information about how fascinating they are, rather than sensationalistic misinformation, then I think spiders are well-suited to serve as tiny ambassadors for wildlife in general.”

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